US Bridges

US 77 over Missouri River & RD

Fair

Woodbury County, Iowa · In Sioux City · Structure no. 000000000052811

Built
1981
44 years old, rebuilt 1983
Condition
Fair
inspected August 2024
Type
Arch - Thru
Steel
Length
1,502 ft
1 main span
Daily traffic
34,600
2022 count
Owner
State
State Highway Agency

About this bridge

US 77 over Missouri River & RD is a steel arch - thru carrying US 77 over Missouri River & RD in Woodbury County, Iowa. It was built in 1981 and reconstructed in 1983, so it is 44 years old, younger than the Iowa average of 45.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 34,600 vehicles a day, roughly 3% of them trucks, projected to reach 34,600 by 2044. The structure is 1,502 ft (457.8 m) long and 68 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesUS 77
CrossesMissouri River & RD
LocationIn Sioux City
RouteU.S. Route 77
CountyWoodbury County
StateIowa
Coordinates42.48752, -96.41357
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating82.2 US tons
Inventory rating46.3 US tons

Structure

Structure typeArch - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+7 approach)
Design loadHS 20
Structure length1,502 ft (457.8 m)
Longest span425 ft (129.5 m)
Deck width68 ft (20.6 m)
Roadway width63 ft (19.2 m)
Vertical clearance over deck17 ft (5.2 m)

Traffic and service

Average daily traffic34,600 (2022)
Projected traffic34,600 by 2044
Trucks3%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway and waterway
Detour if closed6.2 mi (10 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was US 77 over Missouri River & RD built?

It was built in 1981, making it 44 years old in 2025. It was reconstructed in 1983.

What condition is US 77 over Missouri River & RD in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in August 2024.

How much traffic does US 77 over Missouri River & RD carry?

About 34,600 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is US 77 over Missouri River & RD?

The structure is 1,502 ft (457.8 m) long with a longest span of 425 ft (129.5 m) and a deck 68 ft wide.

Who owns US 77 over Missouri River & RD?

It is owned by the State Highway Agency.